Apparatus for temporarily storing thread in a spindleless spinning machine

ABSTRACT

Method and apparatus for rejoining broken thread in a spindleless spinning machine wherein the thread is formed in a turbine and withdrawn on to a spool. The breakage of the thread is sensed and in response thereto the spinning operation is stopped and the thread reversed into the spinning turbine. Upon the restarting of spinning, means are provided to temporarily store a loop of thread in order to compensate for the faster action of the spinning turbine than that of the withdrawing spool. The means comprise a hollow suction chamber located adjacent the path of the thread.

Unite States Patent 1 1 1111 3,842,579

Bartling Oct. 22, 1974 APPARATUS FOR TEMPORARILY 3.601.969 8/1971 SUSumlCl 111.... 57/80 3.662.532 5/1972 Stahlecker 57/80 STORING THREAD IN ASHNDLELESS 3.685.267 8/1972 Landwehrkamp 57/80 SPINNING MACHINE GerhardBartling, Burgstall/Murr, Germany Assignee: SKF Kugellagerfabriken GmbH,

Schweinfurt, Germany Filed: Apr. 20, 1973 Appl. No.: 353,109

Inventor:

References Cited UNITED STATES PATENTS 7/1969 Makcham ct al. 57/81 X2/l970 Landwehrkamp et 21].... 57/5889 X 8/197] Schiltknccht 57/5889S-uo N Primary ExaminerDonald E. Watkins Attorney, Agent, or Firm-MurraySchaffer [57] ABSTRACT Method and apparatus for rejoining broken threadin a spindleless spinning machine wherein the thread is formed in aturbine and withdrawn on to a spool. The breakage of the thread issensed and in response thereto the spinning operation is stopped and thethread reversed into the spinning turbine. Upon the restarting ofspinning, means are provided to temporarily store a loop of thread inorder to compensate for the faster action of the spinning turbine thanthat of the withdrawing spool. The means comprise a hollow suctionchamber located adjacent the path of the thread.

' 9 Claims, 2 Drawing Figures Pmmmnm 2 21374 SHEEI 1 0f 2 APPARATUS FORTEMPORARILY STORING THREAD IN A SPINDLELESS SPINNING MACHINE BACKGROUNDOF THE INVENTION The present invention relates to apparatus fortemporarily storing a surplus length of thread in a spinning machine andin particular for the storage of thread at the start up of a high speedopen end spindleless spinning machine.

It is known to provide spinning machines, and in particular an open endspindleless spinning machine in which a turbine twists the fiber into anelongated thread or yarn, with a dancer roller and lever to create areserve of thread yarn. The dancer roller and lever is generally locatedbetween two means of the machine which hold the yarn under tension afterit is formed on the turbine. For example, the dancer roller and levermay be arranged between the take up nip rollers and the wind up spool.The dancer roller is adapted to pull the thread laterally of thestraight line connection between these two means so that it may be moreor less deflected from its general direction of run. In this manner byvarying the pull and the angular velocity of the dancer roller thethread may be held at a more or less constant tension so that on the onehand the possibility of thread breakage is greatly reduced and on theother hand a desirable reserve length of thread can be obtained betweenthe two means.

It is further known to provide in open end spindleless spinning machinesmeans for producing a thread reserve of suitable length and for holdingsaid thread reserve in a position at which the subsequently spun threadcan be joined to it so that the subsequent thread can be pulled onto thewind up spool itself. Thus, after a thread breakage, the spinningmachine can be automatically put into respinning operation and the newlyspun yarn joined to the end of the previously spun yarn, without theneed for the machine operator to manually withdraw the newly spun threadand tie it to the thread already wound on the winding spool. In thisknown apparatus the normal drive and operation of the spinning machineaccomplishes this operation automatically. In general, this apparatus isquite satisfactory and provides suitable means by which a thread reservecan be created for the proper resumption of spinning. On the other hand,the resumption of spinning requires the wind up spool and the take upnip rollers to be brought up to their optimum operating speed over aperiod of time so that the proper tension is maintained on the thread.In general, however, the wind up spool requires a greater length of timeto reach its normal speed than do the take up nip rollers. Thus, uponresumption of spinning after a break defect has been corrected, asurplus of thread is created which cannot be wound on the spool untilthe spool reaches its normal speed. The present machines such as thosedescribed above do not satisfy the condition and do not provide meansfor storing the surplus of thread upon the start up of spinning and thusconstitute a disadvantage to the proper winding of the thread.

It is an object of the present invention to provide apparatus forspindleless spinning machines which remove the disadvantages of theknown devices and in particular which provides apparatus for temporarilystoring an excess of thread length created when the take up nip rollerspeed is higher than the speed of the winding spool and which stores theexcess until the wind up spool reaches its normal drive of velocity.

It is a further object of the present invention to provide temporarystorage means for accumulating excess length of thread, whichcontinuously operates on the running thread which has only a slight butcontinuous effect on the thread so that the excess thread length can beconstantly but slowly built and reduced in accordance with the operationof the machine and the tension on the thread.

The foregoing objects, other objects, as well as numerous advantages ofthe present invention will be seen from the following disclosure.

SUMMARY OF INVENTION According to the present invention temporarystorage means for storing excess length of thread formed on the turbineof an open ended spindleless spinning machine is provided comprising ahollow chamber 10- cated between the turbine and the wind up spool ofthe machine. The hollow chamber has an opening located adjacent the pathof the thread and is connected to a source of suction. The magnitude ofthe suction being selected such that when the tension on the threadfalls below a predetermined value the thread is caused to be drawn as aloop into the hollow chamber. Preferably the chamber is formed as a tubeopen at both of its ends. One end of the tube is connected to the sourceof vacuum, such as compressor pump reservoir, etc. The other end of thetube is provided with a suction nozzle which preferably is formedintegrally with the tube itself.

It is most advantageous to arrange the nozzle of the tube adjacent theline of thread movement between the take up nip rollers and the windingspool so that the suction constantly acts on the thread. It is furtheradvantageous to utilize the source of vacuum already existing for thespinning machine which supplies the spinning turbine and spinningchamber with its own vacuum to withdraw the waste thread and wastefibers. Spinning machines are normally provided and exist with suitablesource of vacuum.

Full details of the present invention are given in the followingdescription and are shown in the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a schematic side view of a spindleless spinning machineshowing the apparatus of the present invention combined therewith, and

FIG. 2 is an enlarged schematic view of a further embodiment of thepresent invention.

DESCRIPTION or INVENTION As seen in FIG. 1, a spindleless spinningassembly, generally depicted by the numeral 1, of the type shown anddescribed in copending application Ser. No. 264,527 filed on June 20,1972, comprises a rotating spinning turbine 9 mounted within the chamberof an enclosed housing. The assembly produces in the known manner athread 3 which pulled through an outlet channel or tube 8. In accordancewith the present invention an electrical sensor, such as aphoto-electric cell 2 cooperating with a light source, or similar deviceis mounted on the tube 8 to sense the continuity of the thread 3. Thethread 3, in normal operation (FIG. 1),

is withdrawn from the spinning turbine 9 by a pair of take up niprollers 4a and 4b which are biased by a spring 6 to press against eachother. The rollers 4a and 4b have a smooth outer circumference and aredriven by a continuously clockwise rotating wheel or roller whichextends across and in contact with each of similar nip rollers employedalong the spindle bank of a multiple spinning assembly machine. Theroller 4a is mounted at the end of a lever which is biased by a spring12 to pivot about a point 13 into normal operating engagement with thedrive roller 5. The roller 4b is mounted at the end of a bell crank 16also pivoted at the point 13 and biased by a spring 6 to press theroller 4b against the surface of roller 4a for conjoint swinging androlling.

The thread 3 passes over a dancer roller and arm 11 which is adapted tooscillate and resiliently accumulate a length of thread in reserveduring the operation of the apparatus. The thread 3 then passes over agrooved drum 10 on which a reel or wind up spool 21 rests for freerotation. The grooved drum 10 rotates the spool 21 and acts to apply thethread in an even manner across it. The drum 10 and therefore the spool21 abutting against it is driven by the common drive by the roller 4aabutting against roller 5 via a transmission such as a chain or belt 14arranged on the axle or shaft for roller 4a.

The electric sensor 2 is connected to a control circuit schematicallyshown by the numeral 20. The control circuit may employ one or morerelays, solid state amplifier circuits, timing devices, etc. Thephotoelectric sensor suggested is of conventional construction producingan electric signal output on sensing the presence or absence of a givenobject in line with it. In the present situation should the normaloperation of the spinning assembly be disturbed by a break in the thread3,

the sensor 2 produces a signal passing to the control circuit 20.Operatively connected to the control circuit are a pair of brake means17 and 18 which are mounted respectively to stop the rotation of eitheror both of the rollers 4a and 4b and the groove drum 10 on command ofthe control circuit on receipt of a signal indicating a break in thethread. A two stage actuator 19 such as a double winding solenoid withmagnet core is mounted generally perpendicular to the long arm of thebell crank 16 and is connected to it by a bolt and pin 39. The actuatoris adapted to move the lever 16 and to hold it securely against theroller 4a so that both the rollers 4a and 4b come free of the drivingroller 5 simultaneously. Both rollers 4a and 4b are stopped by brakingmeans 17. This stops the movement of the thread 3 and maintains a lengthof the thread hanging below the rollers 40 and 4b. The movement of thelever .16 by the actuator 19 is limited by a micro-switch 38 or the likearranged at a predetermined distance from the edge of the lever 16. Instopping the rollers and the grooved drum 10 the dancer roller and arm11 acts to maintain a sufficient length of thread in reserve.

Simultaneously with the stopping of the thread movement, the controlcircuit 20 causes a normally closed resiliently biased clutch orcoupling to open by energizing its solenoid coil 24. The clutch 25normally operates the paired feed rollers 26 by which the raw fiber band27 is fed to the spinning chamber. After a predetermined time delay, thecontrol circuit 20 activates a cutting element 7 which is arrangedbetween the spinning assembly 1 and the rollers 4a and 4b. The cuttingelement 7 is mounted at the end of the tube 8 in axial alignment withthe thread and may be of conventional construction known to thoseskilled in the art. The spinning turbine 9 is maintained under vacuumvia a conduit 31 extending from a source of vacuum 32 such as areservoir or air pump. The piece of thread 30 cut by the cutter 7 isthus carried away together with the other fiber particles, pulp, etc.formed in the spinning chamber.

The spinning assembly housing is pivoted at one end 29 and is swung fromits other end by a second solenoid or similar actuator 28. The drivewhorls for the spinning turbine 9 and the fiber picker and looseningrollers, generally depicted by the numerals 26 and 33, extend out of thehousing solenoid 28 actuated by a signal from the control circuit 20sothat the housing is pivoted simultaneously with the application ofbrakes 17 and 18 and the actuation of the first solenoid 19 so that thespinning turbine 9 and the fiber pickers 33 are also disengaged fromtheir drive means.

As soon as the housing pivots under action of actuator 28, it releases asecond micro-switch 36 which causes the control circuit 20 to furtheractivate the actuator 19 to pull the upper arm of bell crank 16 furtherto the right. This latter movement causes the roller 4b, which is of thesame diameter as its companion roller 4a, to engage the surface of thedrive roller 5. On reaching this position a latch 23 falls behind theupper arm of the lever 16 overcoming the effect of spring 12 and holdingthe lever 16 in the position where roller 4b is rotated by thecontinuously rotating drive roller 5. The brakes 17 and 18 aresimultaneously released. The rotation of the roller 4b is thus reversedand counter to its normal operating direction, i.e.: when roller 4a isin contact with the roller 5, thus causing the completed thread 3 to bepulled downwardly off the spool 21. This causes the spool 21 to alsoreverse direction. The slot 39 is of a length that after a latch 23engages the lever, the actuator 28 may be returned to its forward ororiginal position.

Through the aforedescribed switching process, the thread 3 with its endis moved backwardly through the tube 8 into the spinning chamber withoutactual reversal of any of the drive means or special operation of theother parts. At the instant the backwardly moving thread 3 passes thephoto sensor 2, a new impulse signal is sent to the control circuit. Thecontrol circuit 20 in turn causes the coupling 25 to close, and thesolenoid actuator 28 to release the housing all of which places thefiber feed rollers 26, the picker 33 and the spinning turbine back intoaction, even while the thread continues to reverse. Simultaneously, anadjustable impulse generator 37 which is driven by the common drive 5closes and begins producing a series of impulses.

The fiber subsequently fed from the feed rollers 26 is spun, inconventional manner by centrifugal action against the inner wall of thespinning turbine 9, and is drawn off from the so-called binding orsplicing point which is fixed within the general limits on the face ofthe spinning wall. The constant path and distance over which thread 3must be returned between the thread sensor 2 and the binding point ofthe spinning turbine can be derived as a ratio of or a multiple ofimpulses generated by the impulse generator 37, which multiple can bepredetermined. Thus, after a predetermined number of pulses indicativeof the time necessary for the thread to come back to the binding pointand automatically splice itself, the control circuit is caused toenergize a magnet 34 which lifts the latch 23 releasing the lever 16,which for all the preceding time was holding roller 4!; against thedrive roller 5. On release of lever 16 roller 41; is freed allowing theroller 4a to return into contact with the drive 5, thus placing theentire apparatus back into its normal production position. During thisentire rebinding or splicing operation, the take up roller 21 slips inreverse direction over the grooved drum 10, on action of the downwardlymoving thread, permitting the dancer arm 11 to pull and maintainadequate reserve yarn.

The operation of the aforementioned device can be further ascertained byreference to Ser. No. 264,527. The device functions in the same manneras was earlier discussed in the introduction to this specification. Thedisadvantage earlier disclosed exists in that when knitting is initiatedor resumed after the removal of the cause of the thread breakage, thewind up spool 21 because of its previous reversal of rotation firstslides and then only after the elapse of a period of time reaches itsfull rotational speed, while simultaneously the take up rollers 4a and4b reach their full operating speed practically at once. This conditioncannot, however, be eliminated since it is essential in order to arriveat the desired quality of the newly spun thread especially the desiredthickness thereof which, of course, depends from the speed of rollers 4aand 4b. In this manner, during the time it takes for the wind up spoolto reach its operating speed, the take up nip rollers 4a and 4b producean excess of thread which is fed somewhere between the take up rollers4a and 4b on the one hand and the wind up spool 21 on the other hand.This excess thread may become so large that it is only partially takenup and compensated for by the action of the dancer roller reserve lever11 so that unless additional steps are taken the thread becomes so longthat the tension on it falls below the proper and necessary level inorder to have correct reeling of the thread on the spool.

In order to overcome this disadvantage the present invention is providedwhich is shown in the drawings by way of example. As seen in FIG. 1 ahollow chamber 40 is located between the take up nip rollers 4a and 4band the wind up spool 21. The hollow chamber 40 extends horizontally andis connected by suitable conduit means to the same source of suction 32used to evacuate the spinning chamber 9. If desired the hollow chamber40 can be connected to an independent and remote source of suction. Thefront end of the tube 40 is cut at an angle so as to lie substantiallyparallel to the moving thread 3 and forms a mouth 41. The mouth 41 ispreferably extended so as to be close to the thread and therefore thesuction would have a continuous influence upon the moving thread 3.Thus, as the tension on the running thread 3 falls below a predeterminedlevel determined by the degree of suction in the hollow tube 40, theexcess thread would be sucked into the tube 40 in the form of acontinuous loop 42. The decreased tension on the thread would of courseoccur during the time after resumption of spinning and before the windup spool reaches its full operating speed. When, however, the wind upspool 21 reaches its full operating speed which as noted earlier is onlyslightly higher than that of the take up nip rollers 4a and 4b, whichwithdraw the thread 3 from the spinning chamber, this slightly higherspeed leads to a slightly increased tension which is sufficient toslowly but continuously withdraw the loop 42 and the excess length ofthread from the hollow chamber thus allowing the excess lengthtemporarily stored in the chamber 40 to be slowly reeled onto the spool21. The length of the loop 42 is continuously reduced over the period oftime until the thread 3 is again withdrawn in a straight line betweenthe rollers 4a and 4b and the dancer roll 11. Similarly, the existenceof the continuous suction in the chamber 40 permits the thread to bedrawn into the loop 42 over a continuous period of time thus buildingthe loop 42 slowly, avoiding any ravelling or knotting of the thread.

In FIG. 2 a modification of the apparatus is shown in somewhat moreschematic form although the same reference numerals are used for theapparatus as are shown in FIG. 1. It will be seen from FIG. 2 that thehollow chamber is positioned opposite to the take up rollers 4a and 4balong the contact line of these rollers and is provided with a flaringoutwardly directed funnel-shaped mouth 41. Otherwise the apparatus actsand operates in a similar manner to that as described with regard toFIG. 1.

Preferably, the chamber 40 in either case is formed of a tubular memberwhich may extend to the source of suction 32 or it may be connected atits rearmost end with suitable conduit means connected thereto. Thenozzle 41 at the front end of the tube is preferably made integrallywith the tube although it may be formed of a separate member connectedto it. The source of suction is provided with suitable valve means tocontrol the speed of the air in the tube so that the suction at themouth 41 will cause deflection of the thread 3 into the chamber 40 onlywhen the tension of the thread 3 falls below a certain level. The valvemeans may be provided along the tube since the vacuum provided by thesource of suction normally is predetermined by other requirements of thespinning machine. The air speed in the tube and especially at the nozzle41 thereof is adjusted so that with a given material for the thread andwith predetermined other properties thereof, e.g. the thickness, thedegree of twisting etc., the air speed is always high enough to tautlyretain the loop in the tube as long as the normal working tension of thethread between the take up rollers and the wind up spool 21 has not yetbeen reached. During this period any curling of the loop must beprevented. Alternatively instead of valve means there might be usedinterchangable tubes in order to meet the specific requirementsencountered with various types of threads. Suitable air speeds arehigher than 5 meters per sec and preferably higher than 25 meters persec.

It will be seen from the foregoing that the present invention providessuitable and very effective means for temporarily storing excess threadupon the initiational resumption of spinning in a spindleless spinningmachine. Various changes and modifications will be obvious to thoseskilled in the art and accordingly the present disclosure is intended tobe illustrative only of the present invention and not limiting of it.

Preferably the valve means are designed such that any air stream throughthe tube may be blocked off during normal operation of the spinningmachine. This is also valid in cases where interchangable tubes areused. In this latter case separate valve means may be provided forblocking off the air suction in the tube when no air stream is required.

What is claimed:

1. Apparatus for temporarily storing excess lengths of thread formed onthe turbine of a spindleless spinning machine for subsequent winding ona spool, comprising a hollow chamber located between the turbine and thespool having an opening located adjacent the path of the thread, asource of suction connected to said chamber, the magnitude of saidsuction being selected so that when the tension on said thread fallsbelow a predetermined value, the thread is caused to be drawn as a loopinto said chamber.

2.' The apparatus according to claim 1 wherein the hollow chambercomprises an open end tube connected at one end to the source of suctionand having a nozzle at its other end located adjacent the thread.

3. The apparatus according to claim 2 wherein the nozzle is formedintegrally with said tube.

4. The apparatus according to claim 1 including take up means arrangedto withdraw the thread from said turbine and wherein said nozzle islocated between said take up means and said winding spool.

5. The apparatus according to claim 4 wherein said take up meanscomprises a pair of contacting nip rollers, said nozzle being arrangedfacing said rollers and lying along the line of contact thereof.

6. The apparatus according to claim 1 wherein said source of suction isidentical with the source of suction for evacuating the turbine of saidspinning machine 7. The apparatus according to claim 2 wherein betweenthe source of suction and'the nozzle of the tube there are providedvalve means for adjusting the suction and the air speed in the tube incompliance with the characteristics of the thread spun.

8. The apparatus according to claim 2 wherein at least one of the tubeand the nozzle are exchangable for adjusting the suction and the airspeed in the tube in compliance with the characteristics of the threadspun.

9. The apparatus according to claim 8, characterized in that valve meansare provided for completely disc0nnecting the tube from the source ofsuction during normal operation of the spinning machine.

UNITED STATES PATENT AND TRADEMARK OFFICE QERTIFICATE OF CORRECTION gPATENT NO. 3,842,579

DATED 1 October. 22, 1974 INVENTOR(S) I GERHARD BARTLING It is certifiedthat error appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

On the cover sheet should be inserted rfl FOREIGN APPLICATION PRIORITYDATA April 29 1972 Germany P 22 21 316. 7-26 Signed and gcaled this 0second Day Of September 1975 [SEAL] Arrest:

RUTH c. MASON c. MARSHALL DANN Arresting Officer (mnmissiunvr ofPaIenrsand Trademarks

1. Apparatus for temporarily storing excess lengths of thread formed onthe turbine of a spindleless spinning machine for subsequent winding ona spool, comprising a hollow chamber located between the turbine and thespool having an opening located adjacent the path of the thread, asource of suction connected to said chamber, the magnitude of saidsuction being selected so that when the tension on said thread fallsbelow a predetermined value, the thread is caused to be drawn as a loopinto said chamber.
 2. The apparatus according to claim 1 wherein thehollow chamber comprises an open end tube connected at one end to thesource of suction and having a nozzle at its other end located adjacentthe thread.
 3. The apparatus according to claim 2 wherein the nozzle isformed integrally with said tube.
 4. The apparatus according to claim 1including take up means arranged to withdraw the thread from saidturbine and wherein said nozzle is located between said take up meansand said winding spool.
 5. The apparatus according to claim 4 whereinsaid take up means comprises a pair of contacting nip rollers, saidnozzle being arranged facing said rollers and lying along the line ofcontact thereof.
 6. The apparatus according to claim 1 wherein saidsource of suction is identical with the source of suction for evacuatingthe turbine of said spinning machine.
 7. The apparatus according toclaim 2 wherein between the source of suction and the nozzle of the tubethere are provided valve means for adjusting the suction and the airspeed in the tube in compliance with the characteristics of the threadspun.
 8. The apparatus according to claim 2 wherein at least one of thetube and the nozzle are exchangable for adjusting the suction and theair speed in the tube in compliance with the characteristiCs of thethread spun.
 9. The apparatus according to claim 8, characterized inthat valve means are provided for completely disconnecting the tube fromthe source of suction during normal operation of the spinning machine.